How can we prevent suicide? Major study shows risk factors associated with depression

The statistics for suicide are frightening. According to the WHO, more than 800,000 people commit suicide every year, with perhaps 20 times that number attempting suicide. Suicide is one of the leading causes of death in the young (in the UK for example, it is the leading cause of death in men under 35) see notes, below. Effective measures of suicide prevention are urgently needed.

The BRIDGE-II-MIX study is a major international study looking at depression and suicide. The researchers evaluated 2811 patients suffering from depression, of whom 628 had already attempted suicide. Each patient was interviewed by a psychiatrist as if it were a standard evaluation of a mentally-ill patient. The parameters studied included previous suicide attempts, family history, current and previous treatment, patients' clinical presentation, how they scored on the standard Global Assessment of Functioning scale, and other parameters. The study looked especially at the characteristics and behaviours of those who had attempted suicide, and compared these to depressed patients who had not attempted suicide. They found that certain patterns recur before suicide attempts.

According to author Dr. Dina Popovic (Barcelona):

'We found that "depressive mixed states" often preceded suicide attempts. A depressive mixed state is where a patient is depressed, but also has symptoms of "excitation," or mania. We found this significantly more in patients who had previously attempted suicide, than those who had not. In fact 40% of all the depressed patients who attempted suicide had a "mixed episode" rather than just depression. All the patients who suffer from mixed depression are at much higher risk of suicide.

We also found that the standard DSM criteria identified 12% of patients at showing mixed states, whereas our methods showed 40% of at-risk patients. This means that the standard methods are missing a lot of patients at risk of suicide."

In a second analysis of the figures, they found that if a depressed patient presents any of the following symptoms:

• risky behaviour (e.g. reckless driving, promiscuous behaviour)
• psychomotor agitation (pacing around a room, wringing one's hands, pulling off clothing and putting it back on and other similar actions)
• impulsivity (acting on a whim, displaying behaviour characterized by little or no forethought, reflection, or consideration of the consequences),

then their risk of attempting suicide is at least 50% higher.

Dr Popovic continued: "In our opinion, assessing these symptoms in every depressed patient we see is extremely important, and has immense therapeutical implications. Most of these symptoms will not be spontaneously referred by the patient, the clinician needs to inquire directly, and many clinicians may not be aware of the importance of looking at these symptoms before deciding to treat depressed patients.

This is an important message for all clinicians, from the GPs who see depressed patients and may not pay enough attention to these symptoms, which are not always reported spontaneously by the patients, through to secondary and tertiary level clinicians. In highly specialized tertiary centres, clinicians working with bipolar patients are usually more aware of this, but that practice needs to extent to all levels.

The strength of this study is that it's not a clinical trial, with ideal patients -- it's a big study, from the real world."

Commenting ECNP President, Professor Guy Goodwin (Oxford) said: The recognition of increased activation in the context of a severe depression is an important practical challenge. While many psychiatrists recognize that this constitutes an additional risk for suicide, and would welcome better scales for its identification, the question of treatment remains challenging. We need more research to guide us on best practice.